By Alex, 3/22/2018
First, and most importantly, go outside! This experiment is very messy.
Place the bottle of Diet Coke on a hard, flat surface, and open the cap. (Note: the next step will be a lot easier if you have a funnel or tube of some sort, but this is optional)
Slide the Mentos into the bottle of Diet Coke all at one, and run away!
Watch your geyser go bananas!
Hmm... it seems nobody's added a conclusion for this experiment yet. You can suggest one here.